* (bug 10526) Fix toolbar/insertTags behavior for IE 6/7 and Opera (8+)

* (bug 10526) Fix toolbar/insertTags behavior for IE 6/7 and Opera (8+)
  Now matches the selection behavior on Mozilla / Safari.
  Patch by Alex Smotrov.
* Don't show non-functional toolbar buttons on Opera 7 anymore

Tested and confirmed expected behavior:
* Firefox 2.0 / Mac
* Opera 9.20 / Mac
* Opera 8.0 / Mac
* Opera 7.5 / Mac (no toolbar)
* Opera 6 / Mac (no toolbar)
* Safari 2.0 / Mac
* Safari 3.0.2 / Win XP
* IE 7.0 / Win XP
* IE 6.0 / Win XP

Tested with oddities:
* iCab 3 / Mac (toolbar displays but nonfunctional; seems to have HTML parsing errors unrelated to the JS work)